Dave Vader Posted January 11, 2017 Share Posted January 11, 2017 Some of you may remember the craze about 5 years ago for Ibanez promethean clone amps. I bought one, I'm very fond of it, and it's served me well these last 5 years. However, in the last week the mute switch has started to turn itself on randomly for as long as it wants. I took it apart and cleaned it out with servisol the first time it happened and it seemed to come back. But it happened again at rehearsal last night. It has coincided with me starting to use a behringer BDI in front of it for more EQ as well, but I can't see how that would make a difference. I have seen in the manual that sticking a footswitch in should disable the mute switch - which is all I really want to do at this stage, am going to put a spare jack plug (nothing on it) in the footswitch socket for now. My question is, is this fixable? Can I permanently disable the mute (never use it anyway) or should I be glad that a very cheap amp lasted me 5 years, cut my losses and buy a new one? Any help much appreciated (or offers of old indestructible 300 odd watt amp heads like Trace, Hartke, Peavey etc for not too much money) Quote Link to comment Share on other sites More sharing options...
MoonBassAlpha Posted January 11, 2017 Share Posted January 11, 2017 Are you sure it is the mute switch operating, not the amp going into thermal shutdown, especially if you are eq-in more bass in to it? Just a thought... Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted January 11, 2017 Share Posted January 11, 2017 [quote name='MoonBassAlpha' timestamp='1484148838' post='3213054'] Are you sure it is the mute switch operating, not the amp going into thermal shutdown, especially if you are eq-in more bass in to it? Just a thought... [/quote] ^^ my thoughts also. Quote Link to comment Share on other sites More sharing options...
Dave Vader Posted January 11, 2017 Author Share Posted January 11, 2017 The red light comes on above the mute switch, which made me think it was that. It didn't feel terribly hot either, but it's certainly an option, will run it without the EQ for a few rehearsals (am borrowing a Peavey for gigs from a mate). Didn't think it was clever enough to do a thermal shutdown. I do hope that's what it is though. I'm certainly not going to use it as an excuse to buy a Hartke HA3500 that I saw on ebay and really want now.... Quote Link to comment Share on other sites More sharing options...
Ghost_Bass Posted January 11, 2017 Share Posted January 11, 2017 Only way to know for sure is to take it appart, check the PCB for any signs of oxidation that may cause short circuits near the mute area and replace the mute switch for a new one. If you want to troubleshoot the system before buying a new switch you can remove it from the PCB, find out witch tracks are connected when it's disengaged and do a temporary link with a bit of wire. If it still mutes at will then the problem isn't with the switch. If it doesn't come on again for a period then get a new switch. All these advice imply a certain amount of technical expertise, fi you can't do it safely then have someone else do it for you. Quote Link to comment Share on other sites More sharing options...
neepheid Posted January 12, 2017 Share Posted January 12, 2017 It's started happening on my RedSub 5110 combo (basically the same thing as yours but a different badge and red speaker cone). I think the fault is the headphone jack. Next time it happens, try plugging something in the headphone socket then remove it - on mine the light goes out and the mute comes off right away. I have a 1/2" > 3.5mm adaptor permanently in the Aux in socket so when it happens for me, I just reach over and use that to clear the muting. Quote Link to comment Share on other sites More sharing options...
neepheid Posted January 17, 2017 Share Posted January 17, 2017 [quote name='Dave Vader' timestamp='1484125205' post='3212799'] Some of you may remember the craze about 5 years ago for Ibanez promethean clone amps. [/quote] Did you try to see if the headphone jack was involved in the problem? Would be keen to get a confirmation from someone who appears to have the same issue as me Quote Link to comment Share on other sites More sharing options...
Dave Vader Posted January 17, 2017 Author Share Posted January 17, 2017 I found a Hartke 3500 for 140 quid in a pawn shop in Exeter. I got over excited and bought it. Haven't tried the HB out since, will try it again at some point though. Sorry neep. Was all primed to try the headphone trick though. Quote Link to comment Share on other sites More sharing options...
neepheid Posted January 18, 2017 Share Posted January 18, 2017 [quote name='Dave Vader' timestamp='1484670256' post='3217355'] I found a Hartke 3500 for 140 quid in a pawn shop in Exeter. I got over excited and bought it. Haven't tried the HB out since, will try it again at some point though. Sorry neep. Was all primed to try the headphone trick though. [/quote] No worries. My first proper amp was a 3500 - good amps those. Quote Link to comment Share on other sites More sharing options...
Dave Vader Posted February 1, 2017 Author Share Posted February 1, 2017 Took it back to practice last night, fired it up, mute on. After a few goes at sticking a plug in and out on the headphones it came back - then stayed on all night. Think you might be on to something Neepheid. Ta. Quote Link to comment Share on other sites More sharing options...
neepheid Posted February 2, 2017 Share Posted February 2, 2017 [quote name='Dave Vader' timestamp='1485953042' post='3227943'] Took it back to practice last night, fired it up, mute on. After a few goes at sticking a plug in and out on the headphones it came back - then stayed on all night. Think you might be on to something Neepheid. Ta. [/quote] Nice one, thanks for checking. I think I'll look into replacing that headphone socket, it looks like a standard PCB mount switching jack socket and it's on a handy wee daughterboard (see bottom right of pic below) so assuming there's some adherence to standards then it should be a straight swap. My guess and hope is that the sprung contact(s) which are supposed to be connected when there's nothing plugged into the socket have partially failed, hence why the action of plugging something in there then removing it remakes the connection for a while, until presumably vibration eventually resurfaces the fault. Quote Link to comment Share on other sites More sharing options...
neepheid Posted June 2, 2017 Share Posted June 2, 2017 (edited) Update: I replaced the headphone socket with a Neutrik branded one a couple of months ago (5 year warranty ran out in March). The old one was an absolute bugger to remove, I sucked as much solder off the tabs as I could but in the end I needed to incrementally heat the tags and use a plastic wedge to slowly prise the tags out of the holes. Finally got it out (probably took half an hour in total, moving it a fraction of a mm at a time). By comparison, fitting the new one took about a minute Long story short, I have had no recurrence of the random muting since I replaced the socket. It has been driven hard most weeks at band rehearsal and lugged about all this time. Happy to say I call this one fixed. Probably one of the least difficult things to fix has gone wrong after 5 years. Not bad for such an inexpensive piece of kit. Edited June 2, 2017 by neepheid 1 Quote Link to comment Share on other sites More sharing options...
MoonBassAlpha Posted June 2, 2017 Share Posted June 2, 2017 That's a great update. I'm sure someone will find this useful in the future. Quote Link to comment Share on other sites More sharing options...
Ghost_Bass Posted June 2, 2017 Share Posted June 2, 2017 [quote name='neepheid' timestamp='1496400615' post='3311064'] Update: I replaced the headphone socket with a Neutrik branded one. The old one was an absolute bugger to remove, I sucked as much solder off the tabs as I could but in the end I needed to incrementally heat the tags and use a plastic wedge to slowly prise the tags out of the holes. Finally got it out (probably took half an hour in total, moving it a fraction of a mm at a time). By comparison, fitting the new one took about a minute Long story short, I have had no recurrence of the random muting since I replaced the socket. It has been driven hard most weeks at band rehearsal and lugged about all this time. Happy to say I call this one fixed. Probably one of the least difficult things to fix has gone wrong after 5 years. Not bad for such an inexpensive piece of kit. [/quote] Removing multi-pin components from PCB's may be a real PITA and can take a lot of time, effort and there's the risk of burning the PCB or surrounding components whilst you're trying to remove all the sodder. The trick i use to do this with minimal effort is to simply use a dremmel tool and cut the pins on the component side, after they're all cutted and the component removed i can unsodder and remove each pin individually with minimal heat going in to the PCB allowing it to cool between pins. I've done this recently when i replaced the 12-pin footswitch on my EBS Multicomp pedal. Saved me about half-hour of work. If the component is salvageable then it's a different story and a heat station would come in very handy, specially if the PCB has double side sodder to that component. Quote Link to comment Share on other sites More sharing options...
neepheid Posted June 2, 2017 Share Posted June 2, 2017 [quote name='Ghost_Bass' timestamp='1496402174' post='3311075'] Removing multi-pin components from PCB's may be a real PITA and can take a lot of time, effort and there's the risk of burning the PCB or surrounding components whilst you're trying to remove all the sodder. The trick i use to do this with minimal effort is to simply use a dremmel tool and cut the pins on the component side, after they're all cutted and the component removed i can unsodder and remove each pin individually with minimal heat going in to the PCB allowing it to cool between pins. I've done this recently when i replaced the 12-pin footswitch on my EBS Multicomp pedal. Saved me about half-hour of work. If the component is salvageable then it's a different story and a heat station would come in very handy, specially if the PCB has double side sodder to that component. [/quote] Good shout on cutting the tags, the socket was defective so I wouldn't have cared if it was rendered unusable during the removal. Wish I had thought of that at the time, it would have saved a heap of time and heat. Quote Link to comment Share on other sites More sharing options...
Dave Vader Posted June 12, 2017 Author Share Posted June 12, 2017 Now that is good news. I'm still using switch cleaner and a jack plug in and out of the phones socket. Works most of the time. Might get someone more patient than me to change it out, that would drive me nuts, and I would break it. Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted June 12, 2017 Share Posted June 12, 2017 Now I think on, my Promethean has - a couple of times - gone to 'sleep' for a little while, both times after I plugged my laptop in the line-in to play along with something. Quote Link to comment Share on other sites More sharing options...
Dave Vader Posted April 16, 2018 Author Share Posted April 16, 2018 Update, like Neepheid I took it apart yesterday, and shorted all the contacts on the headphone jack by wiring straight across all three sets. It seems to be okay now, will report back later when I've used it a bit more. I never use headphones, and have no need of a mute while plugged in function anyway, so this was quicker and easier than replacing something I don't need to on the board. Quote Link to comment Share on other sites More sharing options...
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